Up to now, numerous vehicle seats with cushions or cushion parts are known, which have an active or passive seat or backrest aeration. An active seat aeration is a design of the cushion in which air is actively supplied to the cushion or cushion part, for example by means of a fan.
In the case of a passive aeration of a vehicle seat, frequently also referred to as a “passive climate seat”, a vehicle seat is involved in which the supply or removal of air takes place on the basis of the presence of for example aeration ducts and without [an] appliance supplying this air flow.
A cushion for a seat part and/or a backrest of a vehicle seat is known for example from EP 0 936 105 B1, having a ventilation layer through which air can flow and which comprises an air- and water-permeable upper layer and lower layer and spacing web[s] holding the latter at a distance and connected together. In addition, fans or ventilators are provided for blowing air into the ventilation layer. An active aeration is thus involved. The density of the spacing webs is selected to be greater in the longitudinal direction of the cushion than in the width-wise direction of the cushion.
A cushion part for a lower seat part and/or a backrest of an air-conditioned vehicle seat with an air-permeable cushion base part is known from EP 1 417 114 B1. An air-permeable air-conditioning layer, which comprises at least two subsidiary layers, is arranged on the cushion base part. One of these layers, namely the upper layer, has at least proportionately activated carbon which is incorporated in particle form. Both this upper layer and the second subsidiary layer and the cushion base part rest one upon the other in a closed manner, so that an air circulation which should take place by means of openings arranged on the cushion base part has to function through these subsidiary layers. Nevertheless an air flow of this type or an air circulation of this type can take place only to a limited degree when the seat is in a state of occupancy. These layers are then in fact compressed as a result of the weight of the person occupying the seat and they make it more difficult for a flow of air to pass through.
Such a compression of layers arranged at the top and thus the prevention of an air flow are avoided in a simple manner in DE 1 989 306 in that through openings extending in the vertical direction extend over the entire thickness of the cushion and thus terminate on the top side with openings directly at the person who is occupying the seat at that time. As a result, on the one hand the overall appearance of the vehicle seat is adversely affected on account of the visible arrangement of a multiplicity of holes. On the other hand through openings of this type which are accessible in an open manner at the top are susceptible to the accumulation of dirt. For this reason, designs of this type are frequently not desired.
A drawback of the prior art outlined above is that either a relatively complicated design of the cushion is necessary in order to permit at least a passive aeration for example of a part of a vehicle seat, or visually unappealing surfaces of the cushion which are easily soiled are present.